Guest Post: your Thanksgiving / Christmas theropod

Today’s post comes courtesy of Tom Holtz. Obviously being British, Thanksgiving passes me by at the best of times and living in China, I usually only register it when suddenly blogs and websites go very quiet for a few days. However we do usually revel in the Christmas turkey this is hardly an inappropriate post on the theropod ancestry of turkeys.

Thanksgiving is a great opportunity for a reminder of theropod anatomy. Of course, every roast bird offers this possibility, but since the number of people who are likely to encounter a turkey on Thanksgiving is very high, this time of year makes it easy for a vertebrate paleontologist to schedule a timely review of dinosaurian characteristics found in modern birds for their students.

As with any living thing, Meleagris gallipavo has a body that is a record of various traits acquired throughout its long evolutionary history. For example, it has DNA (inherited from the long distant ancestor of all living things), mitochondria and nuclei (from the common ancestor of all eukaryotes), multicellularity (from the earliest animals), enterocoely and determinate embryological cleavage (from the earliest deuterostomes), and on and on up the ever-branching Tree of Life.

Of interest for an instructor in a course on dinosaurs, of course, are traits preserved in a turkey relevant to dinosaur history. A number of paleontologists have used turkeys as teaching tools. For example, the skeleton that is the basis for this figure was taken from a University of California Museum of Paleontology website by Matt Wedel. The figure here (with its label) comes from my own course for non-majors.

Some of the relevant traits aren’t immediately obvious from a roast bird, given that they are typically served headless, footless, featherless, and with the neck separated from the rest of the skeleton. Even so, what osteological features remain records evolutionary events from before the initial divergence of the various dinosaur lineages through the extant (crown-group) bird radiation.

I’ve highlighted many of these. You can see the relevant cladograms and the taxonomy I am using on thesevariousweb pages.

As for flavor, though: given that turkey, chicken, guinea hen, duck, and goose meat all tastes different from each other—and these birds are all within one subclade (Galloanserae) of crown-group birds—it is unlikely that any Mesozoic dinosaur tasted exactly like turkey (or any other modern species of Aves.) Lacking a time machine, we are unlikely to ever know how tasty roasted Velociraptor was.

I suspect given the ‘general interest’ nature of much of my audience this will be rather too technical, but even if the names are meaningless, the sheer number and variety of characters should be interesting and perhaps even convincing in their own right.